EASY
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In photoelectric effect, the kinetic energy of the photoelectrons increases linearly with the frequency of incident light.

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Important Questions on Structure of Atom

MEDIUM
A certain metal has a work function of Φ=2eV. It is irradiated first with 1 W of 400nm light and later with 1 W of 800nm light. Among the following, the correct statement is: [Given:Planck constant h=6.626×10-34 m2kgs-1 Speed of light (c)=3×108 ms-1]
EASY

With regard to photoelectric effect, identify the CORRECT statement among the following:

MEDIUM
Which of the following equations represents the velocity (v) of the ejected electrons when a metal is made to strike with light of frequency v and the threshold frequency of the metal is v0? me=mass of electron and h is Planck's constant).
HARD
The kinetic energy of the photoelectrons ejected from a metal on irradiation with light of frequency 3.8×1016 Hz is K. When irradiated with light of frequency 2.4×1016 Hz, the kinetic energy of the photoelectrons becomes K2. What is the threshold frequency ν0 of the metal?
EASY
The graph that depicts Einstein photoelectric effect for a monochromatic source of frequency above the threshold frequency is
MEDIUM
Maximum number of photons emitted by a bulb capable of producing monochromatic light of wavelength 550 nm is ........., if 100 V and 1 A is supplied for one hour
MEDIUM
The kinetic energy of photoelectrons emitted when the metal M¯  is irradiated with light of frequency 1.6×1016 Hz is twice the kinetic energy of photoelectrons, when the same metal is irradiated with light of frequency 1.0×1016 Hz. What is the work function of the metal M¯ in J?
MEDIUM

The photoelectric behaviour of K, Li, Mg and Ag metals is shown in the plot below. If light of wavelength 400 nm is incident on each of these metals, which of them will emit photoelectrons? [Planck's contant h=6.626×10-34Js; velocity of light c=3×108 ms-1; 1eV=1.6×10-19 J]

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MEDIUM

If p is the momentum of the fastest electron ejected from a metal surface after the irradiation of light having wavelength λ, then for 1.5 p momentum of the photoelectron, the wavelength of the light should be:

(Assume kinetic energy of ejected photoelectron to be very high in comparison to work function)

HARD
The work function of sodium metal is 4.41×10-19J. If photons of wavelength 300 nm are incident on the metal, the kinetic energy of the ejected electrons will be h=6.63×10-34J s; c=3×108  m s-1__________×10-21J
MEDIUM
A metal surface is exposed to 500 nm radiation. The threshold frequency of the metal for photoelectric current is 4.3×1014 Hz. The velocity of ejected electron is ___×105 ms-1 (Nearest integer)
Use:h=6.63×10-34Js, me=9.0×10-31 kg
MEDIUM

What is the work function of the metal if the light of wavelength 4000Å generates photoelectrons of velocity 6×105ms-1 from it?

(Mass of electron  =9×10-31 kg, velocity of light =3×108 ms-1, Planck's constant =6.626×10-34 Js, Charge of electron =6.626×10-34 Js)

MEDIUM
Which of the following elements has the highest work function value?
HARD

When light of wavelength 248 nm falls on a metal of threshold energy 3.0 eV, the de-Broglie wavelength of emitted electrons is ________ Å. (Round off to the Nearest Integer).

[Use : 3=1.73, h=6.63×10-34 Js; me=9.1×10-31 kg; c=3.0×108 ms-1; 1 eV=1.6×10-19 J]

MEDIUM
Assuming that the incident radiation is capable of ejecting photo electrons from all the given metals, the lowest kinetic energy of the ejected photoelectron is observed with which of the given metals?
MEDIUM
If the work function of a metal is 6.63×10-19 J, the maximum wavelength of the photon required to remove a photoelectron from the metal is____nm. Nearest integer)
[Given : h=6.63×10-34 J s, and c=3×108 m s-1]
MEDIUM

The minimum energy that must be possessed by photons in order to produce the photoelectric effect with platinum metal is:

[Given: The threshold frequency of platinum is 1.3×1015 s-1 and h=6.6×10-34Js]

HARD
If the photon of wavelength 150 pm strikes an atom and one of its inner bound electron is ejected out with a velocity of 1.5×107 m/s, what is the energy with which it is bound to the nucleus?
MEDIUM
Which of the graphs shown below does not represent the relationship between incident light and the electron ejected from metal surface?
EASY
Calculate the energy in corresponding to light of wavelength 45 nm: (Planck’s constant h=6.63×10-34Js:speed of light c=3×108 ms-1)